The invention relates to a system for measuring the electrical resistance and the temperature of thin, metallically conductive films deposited on substrates by means of evaporation or sputter-deposition. These measurements are carried out during the film manufacture. An evacuated processing or deposition unit with an evacuatable load lock chamber is employed in the coating. The substrate holder is designed to be movable. The electrical resistance of the film is measured according to the principle of the known two-point or four-point measuring method on a reference substrate with a specific sample geometry and by use of low-resistance contacts. The substrate temperature is measured by means of a resistance thermometer.
In the manufacture of thin, metallically conductive layers, for example for conduction lines in semicondcutor technology or for resistance layers in thin film technology, high demands are made as to the tolerance and stability of the electrical properties. Thus, the absolute values of the electrical sheet resistances of, for example, thin resistors consisting of, for example Cr--Ni, Al--Ta, Cr--Si, may vary only by a few percentage points from charge to charge, and the temperature coefficient of the electrical resistance may often amount to only a few .mu.10.sup.-6 K.sup.-1. Furthermore, the resistance value of the films which are often only 10 nm thick may change only by a few percentage points over a number of years.
In order to achieve this high reproducibility, the residual gas pressure in the evaporation or, respectively, sputter deposition systems must be better than 10.sup.-6 mbar. In order to maintain such a low residual gas pressure even under fabricating conditions, i.e. short cycle time and high substrate throughout, evaporation and sputter deposition systems with vacuum load locks are employed, i.e. the substrates are mounted on a substrate holder such as a pallet with the load lock open. They are subsequently transported into the actual deposition chamber by means of the pallet with the load lock closed--after the load lock reaches a specific final pressure. Such a deposition system with a load lock chamber is known from German OS No. 29 29 804, incorporated herein by reference. The substrates must still be moved during the deposition in order to attain the necessary homogeneity of the layer. This means that there is no specific or fixed position of a substrate in the deposition chamber.
In order to be able to precisely determine the end of the deposition process, a resistance measurement during the deposition would be of great technical advantage. Accordingly, one could measure the attainment of the required electrical values, for example of the sheet resistance. Moreover, it would even be possible to follow and appropriately control the film growth practically from the first monolayer, as is proposed in German patent application No. P 30 04 149.7, corresponding to U.S. Ser. No. 231,885 now U.S. Pat. No. 4,331,702 filed Feb. 5, 1981, and incorporated herein by reference.
Since the substrate temperature during the deposition (20.degree. C. through 500.degree. C.) can noticeably influence both the electrical properties as well as the stability of the film, knowledge of this type is also of significance for a reproducible deposition process.